A blower device for expanding continuous webs of filter material

摘要

Compacted filter tow is drawn out initially into continuous webs (7) and then expanded by a blower device (1) comprising at least one blower unit (12) connected by way of an air delivery duct (13) to an air flow control system (14) equipped with at least two open/close valves (16) controlling relative air outlet ducts (17); also forming part of the air flow control system (14) is a plenum chamber (19), operating in conjunction with a pressure control circuit (20) in such a way as to maintain a steady equalizing pressure internally of the chamber (19).